Dear Advaitnath, you haven't mentioned your subjects in 10+2. But if your subjects are Physics, Chemistry, Biology and Mathematics, you should clearall of those subjects in your Board exams. Later when you are appearing for NEET, you can omit Mathematics from your preparation and prepare only Physics, Chemistry and Biology because NEET has no Mathrmatics syllabus. But for you to appear for NEET, it is.important you clear all your 12 subjects whether they are included in NEET syllabus or not.